9 voly battery >>> pos = forward speaker movement

 

yep a trick i finally learned...lol

 

Used that method for years when I used to install. We just used whatever battery the drill was.. Back then 12-14.4v. heh.

 

Haha yeah in a pinch the 12-14 volt is ok but definitely DONT make using that large of a battery as the norm, you are MUCH better off with something smaller like a double a battery as it is less stress on the speaker...Remember speaker dont like dc current very much ESPECIALLY large amounts of dc current PLUS if you for whatever reason grab a wrong wire that happens to be an airbag wire it WILL go boom...Ive seen it in person and damn near pissed myself from laughing so hard

Check this out my old boss was training a new guy and told him to use his 9.6 volt drill battery to pop the speaker to check polarity, WELL my old boss was holding the door and i happened to be a new Mercedes with airbags in the door panel itself "my boss was all of 4'11" tall and MAYBE 90 lbs, WELL the new guy grabbed the airbag wires going into the door while my boss had the door panel off and was holding it against his chest so he could physically see the speaker to make sure the polarity was correct, As soon as the newb tagged the airbag wire the airbag blew up into my bosses chest and literally launched him a good 5 feet across the shop floor...I was literally in TEARS from laughing so hard at the fact of watching him fly across the shop HAHAHAH it was BY FAR he funniest god damned thing I have ever seen in all my years doing this.

 

Damn I wish u had a vid

 

Does the new guy still work there?

 

Hold the speaker so you can see the back, rotate it until the terminals are at 6 0'clock, terminal on the right is +ve. Only speaker I have ever found this not to be the case with was some old Lanzar mid.

 

* Special note * do not use any more than 1.5 v as it may damage the speaker coil

Haha I'll give you $20 if you can blow a speaker with a 9v battery. :laugh:

 

...Is method #2 purposely vague? Am I to assume when positive terminal of speaker touches positive post of battery. The speaker will emit sound? And only when connected positive to pos. and neg. to neg?

 

No, it won't emit sound (well, you might hear a crackle upon connection) -- the point is to observe which direction the cone moves. If it moves out, then that means the + of the battery is hooked to the + of the speaker (and minus to minus). If it moves the other way, then that means the reverse is true.

 

...Thanks for your clarification. Most appreciated!

 

What about tweeters?

 

Me too.

 

... But really stay on 1.5 V, for tweeters !

 

But tweeters have very low xmax, can you see cone excursion with 1.5v?

 

LOL quite a good remark !

But DC will move them far enough to be noted.

Don't exagerate voltage, as their coil wire is very thin and may burn easily. You should even think about adding a current limiting resistor in serial with the battery (about 100 ohms will be enough).

A lot of tweeters only have soldering points as terminals and are generally provided with short cables soldered on, generally color coded anyway

In case the cables are gone, then polarity is generally engraved near the soldering points. Or you may have a red ink spot, or something like that...

 

I never try to find the positive terminal for the tweeter and never will.
What I need is just listen for the best acoustic polarity.

Kelvin

 

Well, actually...

I was just wondering if any phase inversion would have any perceivable effect from a tweeter.

The reproduced frequencies are so high, and the wavelengths so short that moving your head just an inch has more effects than inverting the terminals (actually something like 100000 times more effective at 4 kHz), so...

... Wanting to determine its "exact" (let's say "factory" instead) polarity is actually as useless as thinking you could hear a better sound by inverting the polarity.

That's why playing with the phase a subwoofer can easily trick the listener into feeling the bass coming from the front of the car while they are played from the trunk (a short range of frequencies of very long wavelenghts), while you'll have to use a time alignment device to shift all of the frequencies played by a tweeter if you want to compensate the distance.

 

Z80_Man
I think inverted phase can make sound worse (but this effect can be different from case to case, from noticable to not). So it is better to make thing right at firts, that spend a lot of time for "debug".

 

Reversing the phase for tweets doesn't make anything sound worse. What will happen if you don't have the correct acoustic polarity relative to the midrange is that there WILL be a phase problem near the Xover point = meaning the sound will be drown to the tweeter instead of being high and forward.
Hearing phase problems in the high frequencies is really hard, that's why I focus only on the transition between the midrange and the tweet.

That's why I never try to find the positive wire on a tweeter ; you just need to listen

Kelvin

 

True, and the cutoff frequency will also be be lowest frequencies area for the tweeter.

Moreover, the two speakers curves will overlap there.

Do you personally favor steeper or slower cutoff slopes ?

Some metallic dome tweeters may sound harsh when cut too low, and it often helps to cut them high, above 3.5 kHz, with a soft slope (6 dB). You can leave the medium go full range to the high frequencies, too.

 

thanks for the info! This would help me a lot on installs!!